1. Technical Field
The present invention relates to the optical imaging field and, particularly, to a zoom lens module and a zoom camera module having the same.
2. Description of Related Art
With the development of the optical imaging technology, camera modules are widely used in a variety of electronic devices, such as mobile phones, and Personal Digital Assistants (PDAs).
Since the camera module is desirably to be mounted in small-sized mobile phones or PDAs, a fixed focus lens module is usually adopted due to its relatively small thickness. However, images captured by a camera module with a fixed focus lens module tend to be poor in quality. This is partly due to the fixed focus lens module, which is incapable of adjusting a focal length to make a good-quality image.
A conventional zoom camera module usually uses an actuator, such as a step motor to zoom. In order to zoom, the actuator drives a first lens group to move along an optical axis relative to a second lens group. Such a zoom camera module inevitably has a relatively large thickness in a direction of the optical axis. Accordingly, such a step motor is not suitable to be used in a mobile phone or PDA, which requires a small thickness.
Therefore, a new zoom lens module and a new zoom camera module are desired to overcome the above mentioned problems.